6,511 research outputs found
Supervisory control of remote manipulation: A preliminary evaluation
A system for supervisory control is described, and preliminary results are presented. Supervisory control, where control is traded between man and computer, offers benefits in the control of a remote manipulator. The system has the potential to accomplish sophisticated tasks. It is indicated that supervisory control yields lower task completion times and is preferred over manual control
The 27-28 October 1986 FIRE cirrus case study: Meteorology and clouds
Detailed descriptions of the rawinsonde resolved meteorological conditions (3 hourly soundings) associated with a succession of five distinct mesoscale cirrus cloud regimes, that were intensively observed over a 36 hour period, are given. The synoptic scale systems in which these features were embedded are described and a brief overview of the experiment is given. Regional analyses of the static stability structure and vertical motion are presented and interpreted with respect to the characteristics of the corresponding cloud fields as deduced from satellite and lidar observations. The cloud fields exhibited a high degree of persistent mesoscale organization on scales of 20 to 500 km reflecting corresponding scales of dynamic and thermodynamic structure/variability as on the synoptic scale. Cloud generation was usually confined to layers less than 1 km deep (typically 0.5 km in depth) and cellular organization was evident in most cases irrespective of the thermal stratification. Multilayered development was prevalent (2 to 3 layers) and was associated with vertical structure of the temperature and moisture fields resulting primarily from vertical gradients in horizontal advection
Synoptic conditions producing cirrus during the FIRE cirrus IFO
Although direct observations of cirrus clouds by the FIRE research aircraft were usually confined to the area of Intensive Field Observation (IFO) surface network, these cirrus were generally part of a more extensive zone of upper level cloudiness. It is these large scale patterns of cirriform cloud and their relationship to the corresponding synoptic environment which are the prime focus. Three conceptual models are presented and each of the individual cases are classified into one of these categories. Although the cases manifest significant differences in intensity and small scale structure, it is believed that they are best viewed in this unified context. The descriptions given are mostly qualitative, however, quantitative descriptions of the synoptic control and its relationship to cloud structure for all the IFO cases are summarized. The synoptic situations in which extensive cirriform clouds were observed are classified into three basic types: warm front cases, cold front cases, and closed low aloft cases. A simplified summary of each type of situation is presented
Thermodynamic Limit for Spin Glasses. Beyond the Annealed Bound
Using a correlation inequality of Contucci and Lebowitz for spin glasses, we
demonstrate existence of the thermodynamic limit for short-ranged spin glasses,
under weaker hypotheses than previously available, namely without the
assumption of the annealed bound.Comment: 8 page
Momentum and energy integrals for gravity waves of finite height
1. Introduction. The analytical study of gravity waves of finite height which are periodic and move without change in shape in an ideal irrotational fluid is a subject which has occupied the attention of physicists and mathematicians ever since Stokes (9) published his classic paper entitled On the Theory of Oscillatory Waves in 1847. However, it was not until 1925 that an existence proof for such waves in the case of a basin of infinite depth was published by Levi-Civita (4). The corresponding proof for the case of limited depth was presented by Struik (10) in 1926
A momentum integral for surface waves in deep water
It has been demonstrated by the studies of Stokes (1847) and LeviCivita (1925) that surface waves of finite height which are irrotational and periodic can exist in a liquid under the influence of gravity. Furthermore, it was pointed out by Stokes that such waves produce a transport of mass in the direction of propagation and hence possess a certain horizontal momentum relative to the undisturbed water at great depths...
Estimates of water transport produced by wave action
The writer has received requests on several occasions to give estimates in concise form of the intensity of the transport of water caused by surface waves. It is hoped that the following discussion will be helpful in answering such questions, although it should be pointed out from the beginning that the actual conditions in the oceans depart very significantly from the ideal circumstances presupposed in the theory of the subje\u27ct, so that great caution must be exercised in applying the theoretical results to practical problems in oceanography, pending comparison with observational data
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